You'll find a LOT of help over on the UltimateTV message board (on this very site), but a quick thing to try is to pull the power plug from the UTV and leave it out for several minutes.
Put the power plug back in, and see if that helps. If not, pull ALL cables loose from the unit (even the satellite in RG-6 cables) and let it sit overnight. In the morning, plug in everything and test again.
If none of this works, you may have a hard drive going bad.